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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0b020dc1005b1e9353baa241476ec41fa7ecce8b83e58a8635dc13e5ef79a36' 
  AND token = 'Mc3ZMP8ihyboEnkzxsCHsI/L0HzpHlNn8BFrlSE29k4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}